Actuating mechanism for profile grinders



Sept. l1, 1934. c. H. A. F. L. Ross ACTUATING MECHANISM FOR PROFILE GRINDERS 5 sheets-sheet 1 Filed Feb. 21. 1931 HUIT i. IITH n-ven'or:

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5 Sheets--SheetI 2 Sept. l1, 1934. c. H. A. F. L. Ross ACTUATING MECHANISM FOR PROFILE GRINDERS Filed Feb. 21, 1931 ACTUATING MECHANISM FOR PROFILE GRINDERS Filed Feb. 21. 1931l 5 Sheets-Sheet 3 w VJ BJ MW WAug/s.

sept. '11, 1934.

c. H. A. F. L. Ross ACTUATING MECHANISM FOR PROFILE GINDERS Filed Feb. 21. 1931 5 sheets-sheet 4 'y@ am VMM myfsept. 1v1, 1934.

c. H. A. F. I .Ross v 1,973,507 ACTUATING MECHANISM FOR PROFILE GRINDERS A Filed Feb. 21. 1951 5 sheets-sheet 5 EXHAUST /J/ /A/l. ET

vision oi.' a profiling machine which enables theV Patented Sept. 1l, 1934 AUNITED STA ACTUATING 'ras PATENT `OFI-*ica MEcnANrsM Foa Paois'mil GampEns charles n. vli. F. L. nous, washingto'i. n. c. Application February 21, 1931, serial No. 517,566

9 Claims.

shape and dimensions required by the speciflcations for the particular object. lGenerally twov methods of nishing are employed, either by hand or by the use of a rotating cutting or grinding tool which is moved on the work. Such practice, when carried out in the finishing of a curved or warped surface, results in inaccurate work, as the surface of the nished piece possesses relatively high and low spots. The result attendant upon finishing metal forgings or castings in this manner is to lower the efliciency of the cast.- ing or forgingitself, or the machine, device or structure with which it is associated.

The inaccuracy, just` noted, is particularly encountered in the finishing of curved or warped surfaces. such for example as those met in the formation of screw propellers. Usually the form or shape of a propeller is considered to be based upon a helicoidal surface. While a helix may be inscribed upon paper and the mathematical equationtherefor derived, up to the present it has been impossible to finish the propeller so that it even approximately measures up to its specifications within tolerances usual in machine work.

My invention has for its major object the prowork to be produced within tolerance limits usual to the product of machine tools.

An equally important object of the invention is the provision of a heaozistockl for a profiling machine in which the work being nished is moved longitudinally of the headstock, either towards the forward or rearward end thereof, so that upon either movement the work is brought past a tool maintained in a flxed'position.

Another object of the invention is the provision of a novel fluid pressure operated thrust torque drive for the ram of a pronler.

Still another object of the invention is the provision in aheadstock of a profiler having a thrust torque drive of means for unbalancing the machine and causing the longitudinal and rotative movements of the work carrying arbor to be governed by one template of the desired shape. A further object of the invention is the provision in a profiler of means forvautomatically preventing back lash. Yet a further object of the invention is the devising of a novel means for controlling the fluid pressure employed for actuating the device.

Al still further object of my-invention is the provision of a profiler of simple design which is not only capable of finishing an article having a straight or plane surface, but it may be employed to finish any article having a warped or curved surface.

With these and other objects in view, which may be incident to my improvements, the invention consists in the parts and combinations to be hereinafter set forth and claimed, with the unv derstanding that the several necessary elements, comprising my invention maybe varied in construction, proportions and arrangement without departing from the spirit of the invention and v One manner of practically-carrying out the@ concept of the invention is to couple an arbor carrying the work, undergoing finishing,` to a spindle on the headstock. The spindle, just mentioned, is rotated as well as moved laterally,l by means of a novel thrust torque drive lwhich is actuated by theuse of fluid pressure operated mechanisms. To the spindle there is connected afollower arm whichzis-caused, by unbalancing the spindle itself, to follow a template so as to control the longitudinal and rotative movement of the spindle; as desired.

Included' in the drive mechanism is a novel valve construction employed for the purpose of controlling the admission to and the exhaustionof the working fluid from the actuating mechanism for the device. In addition to this, means vare associated with. the valve construction for varying the speed of the movement of the work as it is rotatedand moved longitudinally of the headstock. In finishing the work, it is moved across the face of a rotating tool mounted upon a stationary base. Not only does the invention contemplate nishing the rough casting or other article as it moves across the tool in one direction,

but it includes finishing it in the opposite direci tion as well.

' in Figure 1.

'Figure 3 is an elevation of the left end of the v machine shown in Figure l.

Figure 4 discloses the right end of the machine shown in Figure l.

Figure 5 is a sectional elevation taken along the line 5-5 of Figure 2.

Figure 6 is a partial sectional elevation taken along the line 6-6 of Figure 2.

Figure 7 is a partial longitudinal section taken along the line 7-7 of Figure 2, with the hood for the machine removed. V

Figure 8 is a detailed plan view of the means for coupling the drive mechanism to the headstock.

Figure 9 is a side elevation of the actuating collar.

Figure 10 is an end velevation of the actuating collar shown in Figure 9.

Figure 11 is a detailed sectional elevation showing the iiuid pressure actuating mechanism for causing movement of the work.

Figure 12 is a detailed view of the valve mechanism employed vfor controlling the movement of the work.

Figure 13 is a detailed elevation, partially in section, of the follower or pitch operating arm.

Figure 14 is a side elevation of the pitch oper# ating arm connected to the spindle. p

Figure 15 is a horizontal sectional view taken along the'line 15-15 of Figure 4, and shows in detail the Valve employed for controlling the in`- let and exhaust of the fluid pressure actuated mechanism.

Figure 16 is a View similar to Figure 1-5, only showing the valve'in a dierent position.

Throughout the drawings similar reference numerals refer to like parts in the different views. A headstock of a proler with a portion of the work arbor secured thereto is shown in Figure 1. For the sake of simplicity, the tailstock of the machine, as well as the cutting or grinding tool, bothof which are positionedlto the right of the headstoclghave been omitted from the drawings.

The headstock comprises a pedestal. 1 which is secured to a suitable bedplate by means oi anchor bolts 2, or any other suitable securing devices. On one side, the top of the pedestal is provided with a longitudinally extending projection 3, which is of a length substantially equal to that of the pedestal. As may be. noted, the projection 3 is provided with a V-shaped groove 4, which cooperates with a gib 5, on the other side of the pedestal so as to form a slideway for a pitch saddle. The gib 5 is maintained in position by a gib retaining bar 6 suitably secured to the pedestal at convenient intervals. By the use of adjusting screws 8, the gib 5 may be adjusted as desired. From an inspection of Figure 6 it will be observed that a slideway 9 is formed 1`etween the groove 4 and the gib 5 in which is slidably mounted a pitch saddle 10 provided with a suitable base or supporting members 11 which cooperate with the side of the groove 4 and the gib 5.

As its name implies, the pitchsaddle 10 is provided with a saddle-like supporting member l2 having a boss 13 provided with an internal bore 14. Within the bore 14 there is positioned a screwjthreaded shaft 16, the outer end of which '-is supported by a bracket 15 having a bearing 17.

As may be noted in Figure 7, adjacent the mouth of the bore 14, there is secured to the pitch saddle a screw threaded plate 18 through which the shaft extends.

Provided upon the end of the shaft there is a suitable actuating handle 19 and also mounted thereon is a graduated wheel 20 associated with the pointer 21, the latter being mounted upon the bracket. By the use of this construction, the pitch saddle may be positioned upon the pedestal as desired, the location of the saddle being determined by the scale wheel 20 cooperating with the pointer 21.

In order to maintain the pitch 'saddle in adjusted positions, the locking member 22 is provided over the gib retaining bar 6 so thatv one of its inner ends may engage a slot 23 in one of the uprlghts 10' of the pitch saddle itself. While any suitable construction may be employed for this purpose, I have disclosed a stud 24, over which the locking member is mounted, the stud being provided with a nut in the form of a locking handle 25 so that the locking device may be loosened or tighened as desired.

Similar to the manner in which the pitch saddle is slidably mounted upon the pedestal, a ram, generally designated by the reference numeral 26, is slidably mounted upon the pitch saddle itself. In accomplishing this, the upper ends of the uprights 10' of the pitcn saddle are provided with gib retaining plates 27 secured thereto by bolts 28 for retaining the gibs 29 against the sides of the ram and providing a suitable slideway there for. The gibs 29 are provided with suitable adjustment screws at suitable intervals, in order to take up for the wear upon the gibs.

y Secured to the pitch saddle, as shown especially well in Figures 1 and 2, are suitable plates 3l, to each of which is connected a tie rod 32, the opposite end of the tie rod being-secured to a cross piece 33 which is attached to a cylinder34. In addition to this, the cylinder is supported at each of its ends upon a suitable base or support 33' which is secured to the pedestal, and in effect` forms an extension thereof. vThe cylinder 34 is provided with a piston 35 and piston rod 36. The cylinder is also provided with a suitable stumng box,- at its end nearest the headstock pedestal, through which the'piston rod 36 extends, the rod also extending through the plate 33. At its free end, -the piston rod 36 is secured to a yoke 37' formed upon an actuator 37. Upon the' actuator member 37 there is-provided a main yoke 51, in order that the actuator member may be supported upon a spindle carried by the ram, for a purpose novato? actuation of the piston 35, movement. of the latter being effected by fluid pressure.means.

To control the admission and exhaustion of the working fluid in the cylinder 34, there is provided upon the pedestal of the machine, a suitable control valve 100, this valve being of the so-called four-way type. As may be noted, the valve is connected to a suitableuid pressure generating system through an inlet conduit or pipe line 101, and an exhaust 102. From the valve-100. pipe lines 103 and 104 conduct the working uld to and from both ends of the cylinder 34. Pipe lines 104 an'd 103 are preferably flexible and are secured by means of suitable couplings 105 to T's 106, thel nipples of which are enthreaded into ports communicating with the interior of each end of the cylinder. Each T 106 is provided with a petcock 107.

The positioning of the valve so as to actuate the piston within the cylinder and hence move the actuator member will be appreciated from a study of Figures 15 and 16. Assume, for example,

v that the piston is at its furthest position towards the right, as shown in Figure 2. With the setting of the valve as shown in Figure 16, the worky Aing uid will ow from the inlet pipe through the pipe line 104 or-the pull conduit with the result that fluid under pressure will be-forced into the right hand end of the cylinder and will move the piston to the left as shown in the dotted line position of Figure 2. At the same time the positioning of the valve as disclosed in Figure 16 results in connecting the push conduit or pipe line 103 with the exhaust side of the valve so that fluid contained in the cylinder orto the left of the piston will be forced through the conduit 103 as the piston moves towards the left to the position indicated in Figure 2. t

By turning the valve at an angle of 45 from that shown in Figure 16 to the position shown in Figure 15, it is evident that the exhaust and in let lines will be closed by the valve and that the piston will remain stationary, while upon rotating the valve through from the position shown in Figure 16, the pipe line 103 will be connected with the inlet side of the valve, while pipe 104 will be connected to the exhaust side of the valve. Positioningthe valve as last described, will result f in moving the piston to the right or towards the tailstock of the machine. p

For working fluid, either compressed air `or liquid may beemployed, however, I prefer the use of oil f or such. When liquid is employed as the working fluid th'e exhaust line may be connected to a suitable sump or reservoir which is in turn connected to a pressure pump, the discharge end of the latter being secured to the inlet line 101. Pressure relief means may be provided by the use of a by-pass line leading from the discharge or high pressure side of the pump to the liquid reservoir. vIn the event that com-` pressed air is employed, 'a suitable compressor may be used to store air in a tank from whence it is led directly from the inlet line to the valve. In the later construction, the exhaust may be directed into the atmosphere or may be led into the atmosphere through an exhaust modifying device. In some instances the exhaust air may bereturnedtothealrtank. l-

For the purpose of providing a thrust torque drive for the headstock, as well as means upon the headstock for carrying the work, the ram is provided at the center of each of its ends with bearing supports 38 and 39, in which are'seated. bearings 40 and 41 for supporting a hollow spin- -ing this purpose is shown particularly Wellin dle 42. The spindle 42 at its end most distant from the actuating cylinder is provided with an extension forming a bearing plate 43 which abuts the end of the bushing 39. The spindle adjacent the bearing plate 43 is screw threaded, as indicated at 44, for a purpose to be hereinafter described.v

The spindle 42 is of a length such that it extends through the bushing 38 towards the rear of the ram for a considerable distance. Suitable thrust bearings 89 of the ball bearing type are l associated with the spindle 42,and are mounted against the bearing supports 38and 39 by the use of collars 90 provided with set screws 91 adapted to engage the spindle itself. In some instances it may be found desirable to thread the spindle, as noted by the reference numeral 45, so as to receive a suitable locking nut adapted to contact with the face of the bearing 40. The construction` just described, will maintain the spindle .in its bearings so that no longitudinal movement thereof is allowed, while at the same time the spindle may be rotated. l

As already pointed out, the spindle 42 is of tubular construction, and at its end adjacent the tailstock, is formed with a short tapered bore, the internal diameter of the rpmainder of the spindle being constant. Within the tapered portion of the spindle there is adapted to be inserted a collet for holding a work arbor 48. In the well known manner of devices of this type, the collet -is internally screw threaded and is adapted to be engaged by the screw threaded end of a drawbar which passes through the hollow spindle and extends beyond its end adjacent the actuating cylinder. To prevent rotation between the collet and the draw bar, the former is provided with any suitable means, such for instance as a keyway, into which is set the end of a guide screw, held in place by any conventional construction such as the head of a retaining screw which abuts against the guide screw.' l

For the purpose of simplifying the drawings, the constructions just mentioned have not been shown in detail. It will, however, be appreciated 120 that by suitably rotating the draw bar the col` let will be forced outwardly so that the work arbor- 48 may be removed therefrom or inserted therein, while rotation of the draw bar in the opposite direction will pull the collet inwardly towards the ram and irmly lock it and thearbor to the spindle so that rotative movement 'ofv the spindle will be transmitted to the arbor.

It has been pointed out that movement of the piston and piston rod will impart a corresponding movement to the actuating member 37, hence it is apparent that if the actuator memberis connected to the ram, a similar movement will be* transmitted thereto. Mechanism for accomplish- Figures 1, 2, and Figures '1 though 10. As may be noted, the actuating member is provided with `a yoke 51 which extends between its sides and may be formed integral therewith. Within the yoke, which is suitably bored, there is mounted a collar 52 which is secured thereto by any suitable means, as for example. the set screws 53. As may be particularly noted in Figure 9, the collar 52 is provided with a slot 54 formed on the periphery thereof and which extends entirely throllh the collar, the slot being in the form of ahe The spindle 42, which is of' considerable length, extends within the collar 52. Upon the spindle there is mounted a screw 55 having an annular y15" screw and roller being engaged by the sides of the slot 54. With this construction, it will be apparent that longitudinal movement of the actuator yoke will impart a. rotative movement to the spindle. i y

For example, assume ,that the piston is moved to the right, as viewed in Figure 1. Such movement of the piston results in a similar movement of the actuator yoke, and hence the spindle 42, which is secured thereto, with the result that the ram is also moved towards the right inasmuch as the spindle is carried thereby in fixed longitudinal relationship therewith. At the same time, however,movement to the right will tend to move the screw and rollers secured to ,thel

spindle downwardly, which effects a clockwise rotation of the spindle, as viewed in Figure 6. Obviously, by suitably choosing the angular position of the slot 54, that is, the helix angle of the slot 54, the force from the piston and piston rod is transmitted into equal components of thrust and torque, the former imparting longitudinal movement of the ram, while the latter imparts rotative movement to the spindle.

The draw bar, previously mentioned in connection with the collet, is of such length that it extends beyond the actuator yoke and collar. As may be noted in Figure 1, there is slipped over the end of the draw bar shaft, adiacent the cylinder, a sleeve 57, one end of which abuts the end of the lspindle within the actuator collar. The

sleeve 57 is secured to the draw bar in any conventional manner and is provided at its end nearest the actuating cylinder with a plurality of holes or openings 58 adapted to receive a tool for rotating the draw bar and hence adjusting the position of the template.

In the parts of the machine heretofore considered, it should be noted that the members comprising the driving mechanism are floated, and that the torque developed is balanced by the thrust. With such an arrangement, it would be impossible to nish a curved or warped surface by passing it across the face of a stationary cutting or grinding tool. To overcome this difliculty so that curved or warped surfaces may be suitably machined, a hood 59 having a semi-cylindrical cross section is positioned over the ram and is secured to the edges of the pitch saddle by any conventional means, as for example, the angle irons 60 and 61, and cooperating bolts 62.

As may be noted in both Figures 1 and 2, the hood 59 is provided with a slotted opening 63 of helical form upon one side of which is positioned a template or former 64 which isdetachably secured thereto by means of the tap bolts 65 or any other suitable securing devices. An edge of the template extends over the side of the slot 63 so as to form a guide for a follower arm, the shape of the template being determined by a line extending around the curved surface of the theoretically finished casting." Also upon the hood, on the opposite side of the opening 63, there is detachably secured a master plate 87 which is employed in a manner to be hereinafter described, for setting the template.

The template 64. is adapted to cooperate with the pitch operating or follower arm to determine the longitudinal and rotative movement of the spindle carrying the work arbor. A follower arm 66 is mounted upon the spindle 42 and is secured thereto in -any conventional manner, as for ex ample, by means of the key 66' engaging the follower arm and a keyway formed in the spindle,

as best shown in Figure 7. As may be` observed, the pitch operating arm is of a. length suillcient to extend through the slot in the hood and near the point where it passes therethrough is provided with a base portion 67, having the bifurcated uprights or arms 68, the upper ends of which are joined by a cross piece 69.

As may be observed in Figures 6 and 7, the frame formed by the uprights and cross piece is adapted to support roller pivot rods 70, the lower ends of which are pivotally mounted upon pivot pins 71 supported upon the base portion 67 of the follower arm adjacent the lowerv ends of the uprights. These pivot pins are maintained in their position .by any conventional means, as for example, the

cotters shown. At a point near the edge of the template, each roller pivot rod is provided with a bearing surface 72 for supporting cam rollers 73, the .end of the pivot roller rod extending through the rollers themselves. Screw threads are formed upon the upper end of the pivot roller shaft so as to receive a nut 74 which is adapted to hold the guide rollers upon their bearings, and in addiwedges, the cam rollers may be adjusted so that they are in contact with the template.

While two cam rollers have been disclosed, and only one template, it is obvious that a second template can be placed upon the left side of the slotted opening 63, shown in Figure 1. A second template may be employed for finishing the reverse side of a casting from that which is machined through the aid of a template on the right, however, for the purpose of simplifying the drawings,

thesecond template has been omitted. When atemplate on the left of the opening, shown in Figure 1, is employed, it functions in a manner similar to the template shown, using the cam roller adjacent its edge.

With the pitch operating or 'follower'arm secured to the spindle, it will be obvious that the floating condition of the device, previously described, is lost, due to the eccentric weight upon the spindle. To overcome and prevent this condition from occurring, there is mounted upon the threaded end of the spindle, a weight wheel 80 adapted to engage the threads 44 formed upon the spindle itself. Carried upon the wheel 80, for offsetting the eccentric weight upon the spindle .due to the pitch operating arm, is a counterbalance weight 8,1, which is secured to the weight wheel by means of bolts 82. Adjustment of the weight 81v is allowed by reason of the slots 83 formed in the weight wheel and in the counterbalance itself.

With the parts of the` machine heretofore described, it will be appreciated that no means have been disclosed for maintaining the cam rollers of the follower arm against the former or template. To accomplish thisso that the longitudinal and rotative movement of the spindle may be such as counterweight 84 is toplace a constant torque on the spindle, as it not only maintains the pitch operating arm against the template, but prevents back lash, as well as allowing the work to stop at 6 the same position upon the| end of a particular stroke, that is, at the saine position for each push stroke and at the same position for each pull stroke.

The conditions just mentioned abov may be 10 best understood by consideration of theV operating principle of the device. Through .the use of a master plate 87, a template 64 is first set upon the hood of the machine at its proper angle. Such a f template is, of course, made by suitable development of the working drawings of the piece or artiv. cle to be finished. The forging or casting undergoing iinishing is mounted upon the work arbor -in the usual manner, and in instances where it is,

'relatively heavy and of considerable size, a tailzo'stock may be employed to support the arbor 48.

-As already mentioned, howeverffor the sake of simplifying the drawings, a tailstock has been omitted therefrom.

: In the event that `the casting being finished is a ias-screw propeller, its hub is slipped overv the arbor 48, which has been previously secured to the i spindle, and a sleeve is then placed over the arbor so as io be iiusii with the hub of the propeller l after which the tailstock is brought into its proper` 3o. position for supporting the arbor.

While a cutting or grinding tool is not shown' in the drawings; it is mounted in a xed position at right angles ,to the arbor shaft, the position of the cutter being changed foreach cut or stroke of the piston. It should be noted that during the cutting stroke, the tool is fixed, its position being changed between strokes of Ythe ram. In operation, the movement of the ram carries the work across the tool irrespective of whether the ram is 40 moved towards the tailstock or a-wayfrom it.

After placing the work uponthe arbor, the pitch satldle is adjusted to the desired position by releasing the locking handle 25 and rotating the actuating handle 19 so as to move the pitch saddle tothe point desired, which is indicated by the pointer 421 cooperating with the scale wheel 20. Positioning of the pitch saddle having been completed, it is again locked in place by means of the handle 25.

Movement of the actuating piston 35 to the right, of course, results in movement of the ram in the same direction and during such movement, the spindle 42 is rotated in a clockwise direction when viewedfrom the cylinder end of the machine. By the use of -the actuator yoke and its coupling to the spindle, as previously described, the force created by the actuation of the piston 35 is broken into equal components of torque and thrust.

Considering that the counterweight 84 is unconnected to the machine, it will be appreciated that the movement of the pitch operating arm will be of a similar degree as that of the spindle.

Hence, if the motion of the cam roller on the follower arm were projected upon a vertical plane, perpendicular to the longitudinal axis of the spind1e,.an arc or a circle would bedescribed.v Inasmuch as the surface undergoing finishing may be of a curved nature, or even a warped surface,

it .is desired to obviate this condition, and for 'this reason, the counterweight 84 is hung upon the weight wheel. It hence results by the use of the counterweight upon' the weight wheel that a constant and independent torque is placed upon the spindle which will cause a cam roller to be in constant contact with the template. 0f course, a similar result would be obtained by securing a spring to the pitch operating arm and to any stationary part of the machine. While such practice may be followed, I prefer the use of the counterweight wheel for the purpose of unbalancing the spindle.l

Due to the independent torque on the spindle created by the use of the counterweight 84, the thrust and torque imparted to the spindle through 35 the actuator member is broken up so that either one of these forces is limited, while the other vis increased so as to allow the pitch operating arm and its cam roller to follow the template. As previously mentioned, a small clearance is provided 90 between the actuator arms 37" and the ribs 26' formed upon the ram 30. Having considered the limitation of the longitudinal and rotative movement of the spindle, caused by the use of the counterweight 84, the purpose of the clearance between the actuator arms and the ribs on the ram will at once be apparent. Should the actuator arms rest upon the ribs 26', the limitation of the movements ofthe spindle, due to the follower arm being in contact with the template, would re- A suit in binding the roller 55 in the slot 54 of the actuator collar. For this reason, a slight amount of play is allowed the actuator collar by providing the small clearance between the actuator arms and the ribs of the ram. Of course, the amount of this play is determined by the amount of clearanceallowed. A

Whilemovement of the ram towards the tailstock has been considered, it is obvious that its movement away from the tailstock will cause the 110,

work to be drawn across the tool in the opposite direction. At the same time, the'constant torque upon the spindle, created by the counterweight 84, will cause the cam roller of the pitch operating arm to follow its template. Cutting or grinding, may hence be carried on upon movement of the ram in either direction. Besides the important function of placing an independent torque upon, the spindle, the counterweight prevents backi'lash in the machine. 120v This, of course, means that in making a new cut orfinishing-an `old cut at the beginning of the piston stroke, the cutter-will not dig into the casting and leave a relatively low spot at the beginning of the` path or section being machined. By

reason of the fact that the cam roller ,is located at a relatively great radius from the spindle, the delicateness and the accuracy of the' adjustment between the cam roller andits template is greatly increased` and at the same time the possi- 130 bility of back lash and inaccuracy inthe finished work is greatly lessened. Such a construction,

as it has been previously pointed out, results in the work being in the same position with respect to the axis of the spindle at the end of each stroke, for example,` the push stroke which moves the work towards the tailstock. The same relation, of course, exists when the ram is at its position nearest the actuating cylinder. Asis well i known, such a condition is of considerable aid in preventing tool breakage.

To cause the operation'of the machine, it is of course, necessary to open the control valve previously described. For this purpose, the valve v 100 is provided with an actuating handle 108 145' which is 'secured thereto by any suitable means, such for example, as the nut 109 secured to the valve shaft 110. In addition to this means for opening and closing the valve, there is also associma with the handle, means for limiting its-15 movement as well as means for automatically closing the same.

The first mentioned means, namely, those for limiting the movement of the valve, are so designed as to limit the va1ve.opening and hence control the amount of working fluid admitted to the cylinder 34 with the attendant result of co trolling the speed with which the work carried upon the work arbor is moved.

Such means for controlling the speed of the movement ofthe work comprises screw threaded lugs 111 mounted upon each side of the axis of the valve handle. Within each lug there is positioned an adjusting screw 112. Upon the valve operating handle, as shown in Figure 12, there is provided bearing or contact plates 113, one of which upon the opening of thervalve is adapted to contact with the end of an adjusting screw 112.

As previously explained, positioning the valve either to the right or left, causes the piston to move either towards the tailstock or away from it. Obviously by turning up the adjusting screws 112 so that they move towards the side of the pedestal, the amount of valve opening that may 5 ing screws so that they are withdrawn from the pedestal, the amount of valve opening may be increased to its full extent, which of course, will result in allowing the maximum amount of working fluid to enter the cylinder and to cause Vthe piston to be moved at a relatively high speed.

It will be appreciated by this construction infinite and steady control of the valve, which results in steady movement of the work, may be obtained.

By suitably positioning the .adjusting screws, the

-speed of the piston in either direction, may be so as to arrest the movement of the piston and consequently the ram and the work upon the work.

arbor. To accomplish this, there is mounted upon the ram itself a suitable cam shaft l114 which is positioned in the bearing support 115 secured to the ram itself. The cam shaft 114 is adjustably mounted by reason of the set screws 116 providedjin the bearing supports sc that itslongitudinal positionl may be adjusted. Adjustably secured to the cam shaft, are two suitable cam surfaces 117 and 118. The cams 117 and 118 are adapted to contact with the end of the valve operating lever 108 so as to close the same at the end of either a forward lor a rearward stroke of -the piston. As may be noted, in Figure 12, the

valve operating handle 108 extends from each side of its pivot so that its inner end may contact' with either of the cam surfaces. y

In the operation of the shut-off device, the

cams 117 and 118 are of course moved with the ram so that if the valve handle is swung vso as to open up the valve, movement of the ram will eventually result in causing one of the cams to contact with either side of the inner end 0f the operating handle. When such contact is made, the further movement of the ram causes the valve to move towards the closed position and when the shut-off is reached, theflow of working fluid into and out of the cylinder will be arrested with the result that the piston stroke isstopped and hence the movement of the work.

Assume, for example, that the adjusting screws 112 are set at the desired position and the ram is at its location nearest the actuating cylinder. When in such position the operating handle of the valve is opened manually and will assume the position shown in the .dotted lines of Figure 12. Upon the opening of the valve in this manner, fluid will be admitted to the left end of the cylinder as viewed in Figures 1, 2 or 11, and the piston will make its "push stroke. Movement of the piston of course results' in movement of the ram, the cam surface 117 finally coming in contact with the valve operating lever. After contact is made with the operating lever, the piston of course is still actuated and the valve is slowly closed until it is in its shut-oilA position, at which point movement of the work is arrested. After the full stroke of the piston, the valve is again opened by hand and is closed by the cam 118 moving it to the shut-oil' position. Of course, it will be well understood that if desired the control valve may be closed by hand at any time.

It is of course obvious that by adjusting the position of the cams 117 and 118, the movement of the piston may be arrested at theend of its full stroke, half stroke, quarter-stroke, or any amount desired. It will be appreciated that the use of the cam surfaces when combined with the adjusting screws of the valve, allows a fineness of adjustment' which is capable of infinite variation so that work may bemoved any longitudinal distance desired at any speed.

As previously described, the follower arm will constantly be in contact with the template 64 and thus rotate and move the work longitudinally the correct amount.' In accomplishing this, it.- is essential that the template be properly set upon the hood of the machine and in the foregoing description it has been assumed that a proper stting of the template has been made. Such a setting of the template must be at the desired angle calculated to effect movement of the work arbor a predetermined amount.

For illustrative purposes, again assuming that a propeller is to be finished, it will be observed that the form and shape thereof is usually considered to be based upon a helicoidal surface. With a surface of this nature, the lead or pitch of a propeller blade vwill of course be the distance that a point on the blade moves forward for one revolution of the propeller. is passed around a cylinder of revolution, the lead of the helix and 4the radius of the cylinder being known, the helix angle may be calculated, its tangent being equal to the dividend of the lead of the helix divided by the circumference of the If a lhelix lar to that noted in the foregoing,'in order that y By the usejof the'master plate 87, previously mentioned, the template may be set at the desired angle which has been calculated. Themaster plate 87 is secured to the hood by means of 6 tap bolts 88 and is positioned upon the side of strictlywith' exceedingly small tolerance limits.' This fact will l the opening opposite to the template 64. In the construction of the master plate, its edge nearest the opening 63 is given a definite angle with respect to the end of the plate. By design thisangle last mentioned, is known. Inasmuch as the angle of the master plate and the angular setting for the tempelate are known or has been calculated, the distance between the two may be readily found by suitable calculations, for any number of points. A suitable number of opposite points on vthe edges of the template and master plate having been determined, the template may be set at its proper angle through the use of measuring gauges, spacers, or other similar devices. With the template correctly positioned, the follower arm will be caused to move the work in accordance with the amount of longitudinal and rotative movement desired.

In many instancesit is desirable to iinish the opposite face o! the casting or work in a different form from that finished by the use of the template 64. For such practice, a second template for the reverse face is employed, this second former being set in a manner similar to that -already described, it being secured upon the actuating-cylinder side of the slot 83. When iinishin the reverse side of the casting, the counterweight 84 is moved so that it is on the opposite side of the spindle axis from that shown in Figures 2 or 4. It will be appreciated that when the reverse side of the casting or other article is iinished, the device operates in a manner like that previously described. It is to be noted, however, that'with the use of two templates, finishing on two faces may be accomplished without the necessity of reversing the work upon the arbor.

Although I have disclosed a machine for nnishing curved and warped surfaces, specific mention being made to propellers, it is to be understood that the device is in nowise limited to work of this particular nature. Obviously articles having diiferentshapedsurfaces and used for other purposes, may be finished upon the machine without departing from the `spirit of the invention and the scope of the appended claims.l

In my invention it is possible to accomplish exceedingly accurate` work which measures up the speciiications set therefor, within be appreciated due to the huid-pressure torque drive of the device which eliminates lossmotion,

insures a steady movement which is easily contrailed, and prevents the occurrence of backlash.

vvi'n ine foregoing description in mindLit wiil be observed that I have devised a novel headstock for a proiller which is not only of simple construction but may be operated with great ease. By providing an unbalanced thrust torque drive with a novel control valve mechanism for actuating and arresting the same, it is possible to cause a pitch operating arm to follow a template of any lshape necessaryto move the work regularly and evenly past the `face of a stationaryv finishing tool. In the device, backlash is eliminated and the machine may be operated so as to produce surfaces within exceedingly small tolerance limits.

' While I have shown and described the preferred Y embodiment of my invention, 1 wish it io be understood that I do not coniine myself to the precise details of construction herein set forth, by way of illustration, as it is apparent that many changes and variations may be made therein, by those skilled in the art, without' departing from the spirit of the invention, or exceeding the scope of the appended claims.

`I claim:

l. In a prole grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof, a spindle rotatively mounted on said ram in a fixed longitudinal relation thereto, a work arbor secured to the spindle, an actuator member provided with a yoke for receiving an end of the spindle, fluid pressure actuated mechanism for moving said actuator member longitudinally of the spindle, means for coupling said actuator yoke to the spindle so as to impart longitudinal and rotative movement thereto, other means associated with the spindle for limiting the longitudinal and rotative movement thereof, a valve mechanism interposed between a source of fluid pressure and said iiuid actuated mechanism for controlling th'e actuation of the same, and still other means associated with saidV ram for automatically closing said valve.

2. In a proiile grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof, a spindle mounted on said ram iny fixed longitudinal relation thereto, a work arbor connected to the spindle, a pitch operating arm secured tothe spindle and adapted to follow a template associated with the headstock mecharying the amount of its opening by a predeter- 1f..

.mined amount, and still other means associated with the ram for automatically closing said valve.

3. In a prciile grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof, a 'spindleI mounted on said ram in fixed longitudinal relation thereto, a work arbo'r connected to the spindle, a pitch operating arm secured toth'e spindle, said pitch operating arm adaptedto follow a template associated with the headstock mechanism, a wheel iixed to one end of said spindle, an actuator member provided with a yoke for receiving the other end of the spindle, fluid pressure actuated mechanism for moving said actuator member longitudinally of the spindle, means for coupling said actuator yoke to the spindle for imparting longitudinal and rotative movement thereto, a weight connected to the A.peripheryof said wheel, a valve interposed beand a plurality of cam surfaces/'associated with said ram for automatically closing said valve.

C 4. In a profile grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof, la spindle rotatively mounted onsaid ram and iixed in longitudinal relation thereto, a

las

Ahood positioned upon the headstock mechanism source of iiuid pressure and said fluid pressure actuated mechanism for controlling the iiow of fluid into and out of said mechanism, means associated with said valve for limiting the amount of .valve opening, and means carried by said ram for automatically closing said valve.

5. In a profile grinder, a headstock mechanism comprising a pedestal, aram slidable longitudinally thereof, a hood positioned over the ram.,

means for adjusting the position of the hood and maintaining it in a fixed position with respect to the pedestal, a spindle rotatively mounted on ksaid -rain and iixed in longitudinal relation thereto, a

work arbor connected tosaid spindle, said hood being provided witha slot adapted to have a pitch operating arm secured to said spindle extend therethrough, a template adjacent one side of said `slot, iiuid pressure actuated mechanism for imparting longitudinal and rotative movement -to said spindle, means for maintaining said pitch operating arm in contact with said template, a valve connected to a source of fluid pressure and to said fluid pressure actuated mechanism for controlling the iiow of iiuid into and out of said mechanism, means associated with said valve for varying the speed of movement of said ram, and other means associated with the ram for automatically closing said valve'.

6. A thrust torque 'drive for the headstock mechanism of a profiling machine, said drive comprising a spindle rotatively mounted upon a ram, said ram being slidable longitudinally oi' said machine, an actuator member provided with a yoke adapted to receive one end of the spindle, fluid pressure actuated mechanism for imparting longitudinal and rotative movement to said member, means for coupling said yoke to said spindle so as to impart a longitudinal and rotative movement thereto, a valve connected to a source of iiuid pressure and said iiuid pressure actuated mechanism for controlling the ilow of iluid into and out of said mechanism, means associated with said valve for predeterminately varying the speed of the movement of said ram, and other means associated with said ram for automatically closing saidvalve.

'1. A thrust torque drive for the headstock of a profile grinder, said drive including a spindle rotatively mounted upon a.y ram slidable longitudinally of the headstock, an actuator member floated upon said spindle, said actuator member provided with a yoke, a collar secured therein, said collar being provided with a slot, an end of the spindle adapted to extend within said collar, coupling means upon the spindle adapted to be engaged by said slot, iiuid pressure actuated mechanism `for imparting a thrusting force to said actuator member longitudinally of the headstock, said thrust being translated by said slot and coupling into rotative and longitudinal movement of the spindle, and a valve connected to a source of uid pressure and said iiuid pressure actuated mechanism-for controlling the admission of fluid into and out oi' the same, means associated with said valve for predeterminately varying the speed of the movement of said ram, and other means associated with said ram for automatically closing said valve.

8. In a proille grinder, a headstock mechanism comprising a pedestal, a ram slidable longitudinally thereof a spindle rotatively mounted on said ram in fixed longitudinal relation thereto, a work arbor connected to the spindle, an actuator member connected to said spindle, fluid pressure actuated mechanism -for imparting a thrusting force to said actuator longitudinally of the pedestal, means for translating said force into components of thrust and torque to be applied equally upon the spindle, and other means forl unbalancing said spindle so as to limit the longitudinal and rotative movement thereof as desired, and a valve for controlling the flow of uid pressure into and out of said fluid pressure actuated mechanism with means associated therewith for varying the speed of the movement of said ram, and a plurality oi' cam surfaces associated with said ram for closing-said valve.

9. In a prole grinder a headstock mechanism comprising a pedestal, a pitch saddle*k adjustably mounted thereon, a ram slidably mounted upon said pitch saddle, a spindle rotatively mounted on said pitch saddle in longitudinal fixed relation thereto, a fluid pressure actuated cylinder with piston and piston rod supported upon said pedestal, said piston rod being connected to an actuator member so as to impart longitudinal movement thereto, said actuator member being pro.

vided withayoke adapted to receive an end of said spindle, means for coupling said spindle to said actuator member so that the thrust of said -actuator member is translated to equal components of thrust and torque on the spindle, and a valve connected toa source of fluid pressure and to each end of said cylinder for controlling the flow of iiuid pressure into and out of said cylinder, means associated with said valve for predeterminately varying its opening, and other means associated with the ram for automatically closing said valve.

CHARLES H. A. F.` L. ROSS.

ioo 

